vpr/src/place/place_macro.cpp - third_party/vtr-verilog-to-routing - Git at Google

 #include <cstdio>
 #include <ctime>
 #include <cmath>
 #include <sstream>
 #include <map>
 using namespace std;

 #include "vtr_assert.h"
 #include "vtr_memory.h"
 #include "vtr_util.h"

 #include "vpr_types.h"
 #include "vpr_error.h"
 #include "physical_types.h"
 #include "globals.h"
 #include "place.h"
 #include "read_xml_arch_file.h"
 #include "place_macro.h"
 #include "vpr_utils.h"
 #include "echo_files.h"


 /******************** File-scope variables declarations **********************/

 /* f_idirect_from_blk_pin array allow us to quickly find pins that could be in a    *
  * direct connection. Values stored is the index of the possible direct connection  *
  * as specified in the arch file, OPEN (-1) is stored for pins that could not be    *
  * part of a direct chain conneciton.                                               *
  * [0...device_ctx.num_block_types-1][0...num_pins-1]                               */
 static int ** f_idirect_from_blk_pin = NULL;

 /* f_direct_type_from_blk_pin array stores the value SOURCE if the pin is the       *
  * from_pin, SINK if the pin is the to_pin in the direct connection as specified in *
  * the arch file, OPEN (-1) is stored for pins that could not be part of a direct   *
  * chain conneciton.                                                                *
  * [0...device_ctx.num_block_types-1][0...num_pins-1]                               */
 static int ** f_direct_type_from_blk_pin = NULL;

 /* f_imacro_from_blk_pin maps a blk_num to the corresponding macro index.           *
  * If the block is not part of a macro, the value OPEN (-1) is stored.              *
  * [0...cluster_ctx.clb_nlist.blocks().size()-1]                                    */
 static vtr::vector_map<ClusterBlockId, int> f_imacro_from_iblk;


 /******************** Subroutine declarations ********************************/

 static void find_all_the_macro (int * num_of_macro, std::vector<ClusterBlockId> &pl_macro_member_blk_num_of_this_blk,
 		std::vector<int> &pl_macro_idirect, std::vector<int> &pl_macro_num_members, std::vector<std::vector<ClusterBlockId>> &pl_macro_member_blk_num);

 static void alloc_and_load_imacro_from_iblk(t_pl_macro * macros, int num_macros);

 static void write_place_macros(std::string filename, const t_pl_macro* macros, int num_macros);

 static bool is_constant_clb_net(ClusterNetId clb_net);

 static bool net_is_driven_by_direct(ClusterNetId clb_net);

 static void validate_macros(t_pl_macro* macros, int num_macro);
 /******************** Subroutine definitions *********************************/


 static void find_all_the_macro (int * num_of_macro, std::vector<ClusterBlockId> &pl_macro_member_blk_num_of_this_blk,
 		std::vector<int> &pl_macro_idirect, std::vector<int> &pl_macro_num_members, std::vector<std::vector<ClusterBlockId>> &pl_macro_member_blk_num) {

 	/* Compute required size:                                                *
 	 * Go through all the pins with possible direct connections in           *
 	 * f_idirect_from_blk_pin. Count the number of heads (which is the same  *
 	 * as the number macros) and also the length of each macro               *
 	 * Head - blocks with to_pin OPEN and from_pin connected                 *
 	 * Tail - blocks with to_pin connected and from_pin OPEN                 */

 	int from_iblk_pin, to_iblk_pin, from_idirect, to_idirect,
 			from_src_or_sink, to_src_or_sink;
 	ClusterNetId to_net_id, from_net_id, next_net_id, curr_net_id;
 	ClusterBlockId next_blk_id;
 	int num_blk_pins, num_macro;
 	int imember;
     auto& cluster_ctx = g_vpr_ctx.clustering();

 	num_macro = 0;
 	for (auto blk_id : cluster_ctx.clb_nlist.blocks()) {
 		num_blk_pins = cluster_ctx.clb_nlist.block_type(blk_id)->num_pins;
 		for (to_iblk_pin = 0; to_iblk_pin < num_blk_pins; to_iblk_pin++) {

 			to_net_id = cluster_ctx.clb_nlist.block_net(blk_id, to_iblk_pin);
 			to_idirect = f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][to_iblk_pin];
 			to_src_or_sink = f_direct_type_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][to_iblk_pin];

 			// Identify potential macro head blocks (i.e. start of a macro)
             //
             // The input SINK (to_pin) of a potential HEAD macro will have either:
             //  * no connection to any net (OPEN), or
             //  * a connection to a constant net (e.g. gnd/vcc) which is not driven by a direct
             //
             // Note that the restriction that constant nets are not driven from another direct ensures that
             // blocks in the middle of a chain with internal constant signals are not detected has potential
             // head blocks.
 			if (to_src_or_sink == SINK && to_idirect != OPEN
                 && (to_net_id == ClusterNetId::INVALID()
 					|| (is_constant_clb_net(to_net_id)
 						&& !net_is_driven_by_direct(to_net_id)))) {

 				for (from_iblk_pin = 0; from_iblk_pin < num_blk_pins; from_iblk_pin++) {
 					from_net_id = cluster_ctx.clb_nlist.block_net(blk_id, from_iblk_pin);
 					from_idirect = f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][from_iblk_pin];
 					from_src_or_sink = f_direct_type_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][from_iblk_pin];

 					// Confirm whether this is a head macro
                     //
                     // The output SOURCE (from_pin) of a true head macro will:
                     //  * drive another block with the same direct connection
 					if (from_src_or_sink == SOURCE && to_idirect == from_idirect && from_net_id != ClusterNetId::INVALID()) {

 						// Mark down that this is the first block in the macro
 						pl_macro_member_blk_num_of_this_blk[0] = blk_id;
 						pl_macro_idirect[num_macro] = to_idirect;

 						// Increment the num_member count.
 						pl_macro_num_members[num_macro]++;

 						// Also find out how many members are in the macros,
 						// there are at least 2 members - 1 head and 1 tail.

 						// Initialize the variables
 						next_net_id = from_net_id;
 						next_blk_id = blk_id;

 						// Start finding the other members
 						while (next_net_id != ClusterNetId::INVALID()) {
 							curr_net_id = next_net_id;

 							// Assume that carry chains only has 1 sink - direct connection
 							VTR_ASSERT(cluster_ctx.clb_nlist.net_sinks(curr_net_id).size() == 1);
 							next_blk_id = cluster_ctx.clb_nlist.net_pin_block(curr_net_id, 1);

 							// Assume that the from_iblk_pin index is the same for the next block
 							VTR_ASSERT(f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(next_blk_id)->index][from_iblk_pin] == from_idirect
 									&& f_direct_type_from_blk_pin[cluster_ctx.clb_nlist.block_type(next_blk_id)->index][from_iblk_pin] == SOURCE);
 							next_net_id = cluster_ctx.clb_nlist.block_net(next_blk_id, from_iblk_pin);

 							// Mark down this block as a member of the macro
 							imember = pl_macro_num_members[num_macro];
 							pl_macro_member_blk_num_of_this_blk[imember] = next_blk_id;

 							// Increment the num_member count.
 							pl_macro_num_members[num_macro]++;

 						} // Found all the members of this macro at this point

 						// Allocate the second dimension of the blk_num array since I now know the size
 						pl_macro_member_blk_num[num_macro].resize(pl_macro_num_members[num_macro]);
 						// Copy the data from the temporary array to the newly allocated array.
 						for (imember = 0; imember < pl_macro_num_members[num_macro]; imember++)
 							pl_macro_member_blk_num[num_macro][imember] = pl_macro_member_blk_num_of_this_blk[imember];

 						// Increment the macro count
 						num_macro ++;

 					} // Do nothing if the from_pins does not have same possible direct connection.
 				} // Finish going through all the pins for from_pins.
 			} // Do nothing if the to_pins does not have same possible direct connection.
 		} // Finish going through all the pins for to_pins.
 	} // Finish going through all blocks.

 	// Now, all the data is readily stored in the temporary data structures.
 	*num_of_macro = num_macro;
 }


 int alloc_and_load_placement_macros(t_direct_inf* directs, int num_directs, t_pl_macro ** macros){

 	/* This function allocates and loads the macros placement macros   *
 	 * and returns the total number of macros in 2 steps.              *
 	 *   1) Allocate temporary data structure for maximum possible     *
 	 *      size and loops through all the blocks storing the data     *
 	 *      relevant to the carry chains. At the same time, also count *
 	 *      the amount of memory required for the actual variables.    *
 	 *   2) Allocate the actual variables with the exact amount of     *
 	 *      memory. Then loads the data from the temporary data        *
 	 *       structures before freeing them.                           *
 	 *                                                                 *
 	 * For pl_macro_member_blk_num, allocate for the first dimension   *
 	 * only at first. Allocate for the second dimemsion when I know    *
 	 * the size. Otherwise, the array is going to be of size           *
 	 * cluster_ctx.clb_nlist.blocks().size()^2 (There are big		   *
 	 * benckmarks VPR that have cluster_ctx.clb_nlist.blocks().size()  *
 	 * in the 100k's range).										   *
 	 *																   *
 	 * The placement macro array is freed by the caller(s).            */

 	/* Declaration of local variables */
 	int imacro, imember, num_macro;
 	auto& cluster_ctx = g_vpr_ctx.clustering();

 	/* Allocate maximum memory for temporary variables. */
 	std::vector<int> pl_macro_idirect(cluster_ctx.clb_nlist.blocks().size());
 	std::vector<int> pl_macro_num_members(cluster_ctx.clb_nlist.blocks().size());
 	std::vector<std::vector<ClusterBlockId>> pl_macro_member_blk_num(cluster_ctx.clb_nlist.blocks().size());
 	std::vector<ClusterBlockId> pl_macro_member_blk_num_of_this_blk(cluster_ctx.clb_nlist.blocks().size());

 	t_pl_macro * macro = NULL;

 	/* Sets up the required variables. */
 	alloc_and_load_idirect_from_blk_pin(directs, num_directs,
 			&f_idirect_from_blk_pin, &f_direct_type_from_blk_pin);


 	/* Compute required size:                                                *
 	 * Go through all the pins with possible direct connections in           *
 	 * f_idirect_from_blk_pin. Count the number of heads (which is the same  *
 	 * as the number macros) and also the length of each macro               *
 	 * Head - blocks with to_pin OPEN and from_pin connected                 *
 	 * Tail - blocks with to_pin connected and from_pin OPEN                 */
 	num_macro = 0;
 	find_all_the_macro (&num_macro, pl_macro_member_blk_num_of_this_blk,
 			pl_macro_idirect, pl_macro_num_members, pl_macro_member_blk_num);

 	/* Allocate the memories for the macro. */
 	macro = (t_pl_macro *) vtr::malloc (num_macro * sizeof(t_pl_macro));

 	/* Allocate the memories for the chaim members.             *
 	 * Load the values from the temporary data structures.      */
 	for (imacro = 0; imacro < num_macro; imacro++) {
 		macro[imacro].num_blocks = pl_macro_num_members[imacro];
 		macro[imacro].members = (t_pl_macro_member *) vtr::malloc(macro[imacro].num_blocks * sizeof(t_pl_macro_member));

 		/* Load the values for each member of the macro */
 		for (imember = 0; imember < macro[imacro].num_blocks; imember++) {
 			macro[imacro].members[imember].x_offset = imember * directs[pl_macro_idirect[imacro]].x_offset;
 			macro[imacro].members[imember].y_offset = imember * directs[pl_macro_idirect[imacro]].y_offset;
 			macro[imacro].members[imember].z_offset = directs[pl_macro_idirect[imacro]].z_offset;
 			macro[imacro].members[imember].blk_index = pl_macro_member_blk_num[imacro][imember];
 		}
 	}

 	/* Returns the pointer to the macro by reference. */
 	*macros = macro;

     if(isEchoFileEnabled(E_ECHO_PLACE_MACROS)) {
         write_place_macros(getEchoFileName(E_ECHO_PLACE_MACROS), *macros, num_macro);
     }

     validate_macros(*macros, num_macro);

 	return (num_macro);
 }

 void get_imacro_from_iblk(int *imacro, ClusterBlockId iblk, t_pl_macro *macros, int num_macros) {

 	/* This mapping is needed for fast lookup's whether the block with index *
 	 * iblk belongs to a placement macro or not.                             *
 	 *                                                                       *
 	 * The array f_imacro_from_iblk is used for the mapping for speed reason *
 	 * [0...cluster_ctx.clb_nlist.blocks().size()-1]                                                    */

 	/* If the array is not allocated and loaded, allocate it.                */
 	if (f_imacro_from_iblk.size() == 0) {
 		alloc_and_load_imacro_from_iblk(macros, num_macros);
 	}

 	/* Return the imacro for the block. */
 	*imacro = f_imacro_from_iblk[iblk];

 }

 /* Allocates and loads imacro_from_iblk array. */
 static void alloc_and_load_imacro_from_iblk(t_pl_macro *macros, int num_macros) {
 	int imacro, imember;
     auto& cluster_ctx = g_vpr_ctx.clustering();

 	f_imacro_from_iblk.resize(cluster_ctx.clb_nlist.blocks().size());

 	/* Allocate and initialize the values to OPEN (-1). */
 	for (auto blk_id : cluster_ctx.clb_nlist.blocks()) {
 		f_imacro_from_iblk.insert(blk_id, OPEN);
 	}

 	/* Load the values */
 	for (imacro = 0; imacro < num_macros; imacro++) {
 		for (imember = 0; imember < macros[imacro].num_blocks; imember++) {
 			ClusterBlockId blk_id = macros[imacro].members[imember].blk_index;
 			f_imacro_from_iblk.insert(blk_id, imacro);
 		}
 	}
 }

 void free_placement_macros_structs(void) {

 	/* This function frees up all the static data structures used. */

 	// This frees up the two arrays and set the pointers to NULL
     auto& device_ctx = g_vpr_ctx.device();
 	int itype;
 	if ( f_idirect_from_blk_pin != NULL ) {
 		for (itype = 1; itype < device_ctx.num_block_types; itype++) {
 			free(f_idirect_from_blk_pin[itype]);
 		}
 		free(f_idirect_from_blk_pin);
 		f_idirect_from_blk_pin = NULL;
 	}

 	if ( f_direct_type_from_blk_pin != NULL ) {
 		for (itype = 1; itype < device_ctx.num_block_types; itype++) {
 			free(f_direct_type_from_blk_pin[itype]);
 		}
 		free(f_direct_type_from_blk_pin);
 		f_direct_type_from_blk_pin = NULL;
 	}
 }

 static void write_place_macros(std::string filename, const t_pl_macro *macros, int num_macros) {

     FILE* f = vtr::fopen(filename.c_str(), "w");

     fprintf(f, "#Identified Placement macros\n");
     fprintf(f, "Num_Macros: %d\n", num_macros);
     for (int imacro = 0; imacro < num_macros; ++imacro) {
         const t_pl_macro* macro = &macros[imacro];
         fprintf(f, "Macro_Id: %d, Num_Blocks: %d\n", imacro, macro->num_blocks);
         fprintf(f, "------------------------------------------------------\n");
         for (int imember = 0; imember < macro->num_blocks; ++imember) {
             const t_pl_macro_member* macro_memb = &macro->members[imember];
             fprintf(f, "Block_Id: %zu, x_offset: %d, y_offset: %d, z_offset: %d\n",
                     size_t(macro_memb->blk_index),
                     macro_memb->x_offset,
                     macro_memb->y_offset,
                     macro_memb->z_offset);
         }
         fprintf(f, "\n");
     }

     fprintf(f, "\n");

     fprintf(f, "#Macro-related direct connections\n");
     fprintf(f, "type      type_pin  is_direct direct_type\n");
     fprintf(f, "------------------------------------------\n");
     auto& device_ctx = g_vpr_ctx.device();
     for (int itype = 0; itype < device_ctx.num_block_types; ++itype) {
         t_type_descriptor* type = &device_ctx.block_types[itype];

         for (int ipin = 0; ipin < type->num_pins; ++ipin) {
             if (f_idirect_from_blk_pin[itype][ipin] != OPEN) {
                 if (f_direct_type_from_blk_pin[itype][ipin] == SOURCE) {
                     fprintf(f, "%-9s %-9d true      SOURCE    \n", type->name, ipin);
                 } else {
                     VTR_ASSERT(f_direct_type_from_blk_pin[itype][ipin] == SINK);
                     fprintf(f, "%-9s %-9d true      SINK      \n", type->name, ipin);
                 }
             } else {
                 VTR_ASSERT(f_direct_type_from_blk_pin[itype][ipin] == OPEN);
             }
         }

     }

     fclose(f);
 }

 static bool is_constant_clb_net(ClusterNetId clb_net) {
     auto& atom_ctx = g_vpr_ctx.atom();
     AtomNetId atom_net = atom_ctx.lookup.atom_net(clb_net);

     return atom_ctx.nlist.net_is_constant(atom_net);
 }

 static bool net_is_driven_by_direct(ClusterNetId clb_net) {
     auto& cluster_ctx = g_vpr_ctx.clustering();

 	ClusterBlockId block_id = cluster_ctx.clb_nlist.net_driver_block(clb_net);
 	int pin_index = cluster_ctx.clb_nlist.net_pin_physical_index(clb_net, 0);

     auto direct = f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(block_id)->index][pin_index];

     return direct != OPEN;
 }

 static void validate_macros(t_pl_macro* macros, int num_macros) {
     //Perform sanity checks on macros
     auto& cluster_ctx = g_vpr_ctx.clustering();

     //Verify that blocks only appear in a single macro
     std::multimap<ClusterBlockId,int> block_to_macro;
     for (int imacro = 0; imacro < num_macros; ++imacro) {
         for (int imember = 0; imember < macros[imacro].num_blocks; ++imember) {
             ClusterBlockId iblk = macros[imacro].members[imember].blk_index;

             block_to_macro.emplace(iblk, imacro);
         }
     }

     for (auto blk_id : cluster_ctx.clb_nlist.blocks()) {
         auto range = block_to_macro.equal_range(blk_id);

         int blk_macro_cnt = std::distance(range.first, range.second);
         if (blk_macro_cnt > 1) {
             std::stringstream msg;
             msg << "Block #" << size_t(blk_id) << " '" << cluster_ctx.clb_nlist.block_name(blk_id) << "'"
                 << " appears in " << blk_macro_cnt << " placement macros (should appear in at most one). Related Macros:\n";

             for (auto iter = range.first; iter != range.second; ++iter) {
                 int imacro = iter->second;
                 msg << "  Macro #: " << imacro << "\n";
             }

             VPR_THROW(VPR_ERROR_PLACE, msg.str().c_str());
         }
     }
 }
	#include <cstdio>
	#include <ctime>
	#include <cmath>
	#include <sstream>
	#include <map>
	using namespace std;

	#include "vtr_assert.h"
	#include "vtr_memory.h"
	#include "vtr_util.h"

	#include "vpr_types.h"
	#include "vpr_error.h"
	#include "physical_types.h"
	#include "globals.h"
	#include "place.h"
	#include "read_xml_arch_file.h"
	#include "place_macro.h"
	#include "vpr_utils.h"
	#include "echo_files.h"


	/****************** File-scope variables declarations ********************/

	/* f_idirect_from_blk_pin array allow us to quickly find pins that could be in a *
	* direct connection. Values stored is the index of the possible direct connection *
	* as specified in the arch file, OPEN (-1) is stored for pins that could not be *
	* part of a direct chain conneciton. *
	* [0...device_ctx.num_block_types-1][0...num_pins-1] */
	static int ** f_idirect_from_blk_pin = NULL;

	/* f_direct_type_from_blk_pin array stores the value SOURCE if the pin is the *
	* from_pin, SINK if the pin is the to_pin in the direct connection as specified in *
	* the arch file, OPEN (-1) is stored for pins that could not be part of a direct *
	* chain conneciton. *
	* [0...device_ctx.num_block_types-1][0...num_pins-1] */
	static int ** f_direct_type_from_blk_pin = NULL;

	/* f_imacro_from_blk_pin maps a blk_num to the corresponding macro index. *
	* If the block is not part of a macro, the value OPEN (-1) is stored. *
	* [0...cluster_ctx.clb_nlist.blocks().size()-1] */
	static vtr::vector_map<ClusterBlockId, int> f_imacro_from_iblk;


	/****************** Subroutine declarations ******************************/

	static void find_all_the_macro (int * num_of_macro, std::vector<ClusterBlockId> &pl_macro_member_blk_num_of_this_blk,
	std::vector<int> &pl_macro_idirect, std::vector<int> &pl_macro_num_members, std::vector<std::vector<ClusterBlockId>> &pl_macro_member_blk_num);

	static void alloc_and_load_imacro_from_iblk(t_pl_macro * macros, int num_macros);

	static void write_place_macros(std::string filename, const t_pl_macro* macros, int num_macros);

	static bool is_constant_clb_net(ClusterNetId clb_net);

	static bool net_is_driven_by_direct(ClusterNetId clb_net);

	static void validate_macros(t_pl_macro* macros, int num_macro);
	/****************** Subroutine definitions *******************************/


	static void find_all_the_macro (int * num_of_macro, std::vector<ClusterBlockId> &pl_macro_member_blk_num_of_this_blk,
	std::vector<int> &pl_macro_idirect, std::vector<int> &pl_macro_num_members, std::vector<std::vector<ClusterBlockId>> &pl_macro_member_blk_num) {

	/* Compute required size: *
	* Go through all the pins with possible direct connections in *
	* f_idirect_from_blk_pin. Count the number of heads (which is the same *
	* as the number macros) and also the length of each macro *
	* Head - blocks with to_pin OPEN and from_pin connected *
	* Tail - blocks with to_pin connected and from_pin OPEN */

	int from_iblk_pin, to_iblk_pin, from_idirect, to_idirect,
	from_src_or_sink, to_src_or_sink;
	ClusterNetId to_net_id, from_net_id, next_net_id, curr_net_id;
	ClusterBlockId next_blk_id;
	int num_blk_pins, num_macro;
	int imember;
	auto& cluster_ctx = g_vpr_ctx.clustering();

	num_macro = 0;
	for (auto blk_id : cluster_ctx.clb_nlist.blocks()) {
	num_blk_pins = cluster_ctx.clb_nlist.block_type(blk_id)->num_pins;
	for (to_iblk_pin = 0; to_iblk_pin < num_blk_pins; to_iblk_pin++) {

	to_net_id = cluster_ctx.clb_nlist.block_net(blk_id, to_iblk_pin);
	to_idirect = f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][to_iblk_pin];
	to_src_or_sink = f_direct_type_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][to_iblk_pin];

	// Identify potential macro head blocks (i.e. start of a macro)
	//
	// The input SINK (to_pin) of a potential HEAD macro will have either:
	// * no connection to any net (OPEN), or
	// * a connection to a constant net (e.g. gnd/vcc) which is not driven by a direct
	//
	// Note that the restriction that constant nets are not driven from another direct ensures that
	// blocks in the middle of a chain with internal constant signals are not detected has potential
	// head blocks.
	if (to_src_or_sink == SINK && to_idirect != OPEN
	&& (to_net_id == ClusterNetId::INVALID()
	\|\| (is_constant_clb_net(to_net_id)
	&& !net_is_driven_by_direct(to_net_id)))) {

	for (from_iblk_pin = 0; from_iblk_pin < num_blk_pins; from_iblk_pin++) {
	from_net_id = cluster_ctx.clb_nlist.block_net(blk_id, from_iblk_pin);
	from_idirect = f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][from_iblk_pin];
	from_src_or_sink = f_direct_type_from_blk_pin[cluster_ctx.clb_nlist.block_type(blk_id)->index][from_iblk_pin];

	// Confirm whether this is a head macro
	//
	// The output SOURCE (from_pin) of a true head macro will:
	// * drive another block with the same direct connection
	if (from_src_or_sink == SOURCE && to_idirect == from_idirect && from_net_id != ClusterNetId::INVALID()) {

	// Mark down that this is the first block in the macro
	pl_macro_member_blk_num_of_this_blk[0] = blk_id;
	pl_macro_idirect[num_macro] = to_idirect;

	// Increment the num_member count.
	pl_macro_num_members[num_macro]++;

	// Also find out how many members are in the macros,
	// there are at least 2 members - 1 head and 1 tail.

	// Initialize the variables
	next_net_id = from_net_id;
	next_blk_id = blk_id;

	// Start finding the other members
	while (next_net_id != ClusterNetId::INVALID()) {
	curr_net_id = next_net_id;

	// Assume that carry chains only has 1 sink - direct connection
	VTR_ASSERT(cluster_ctx.clb_nlist.net_sinks(curr_net_id).size() == 1);
	next_blk_id = cluster_ctx.clb_nlist.net_pin_block(curr_net_id, 1);

	// Assume that the from_iblk_pin index is the same for the next block
	VTR_ASSERT(f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(next_blk_id)->index][from_iblk_pin] == from_idirect
	&& f_direct_type_from_blk_pin[cluster_ctx.clb_nlist.block_type(next_blk_id)->index][from_iblk_pin] == SOURCE);
	next_net_id = cluster_ctx.clb_nlist.block_net(next_blk_id, from_iblk_pin);

	// Mark down this block as a member of the macro
	imember = pl_macro_num_members[num_macro];
	pl_macro_member_blk_num_of_this_blk[imember] = next_blk_id;

	// Increment the num_member count.
	pl_macro_num_members[num_macro]++;

	} // Found all the members of this macro at this point

	// Allocate the second dimension of the blk_num array since I now know the size
	pl_macro_member_blk_num[num_macro].resize(pl_macro_num_members[num_macro]);
	// Copy the data from the temporary array to the newly allocated array.
	for (imember = 0; imember < pl_macro_num_members[num_macro]; imember++)
	pl_macro_member_blk_num[num_macro][imember] = pl_macro_member_blk_num_of_this_blk[imember];

	// Increment the macro count
	num_macro ++;

	} // Do nothing if the from_pins does not have same possible direct connection.
	} // Finish going through all the pins for from_pins.
	} // Do nothing if the to_pins does not have same possible direct connection.
	} // Finish going through all the pins for to_pins.
	} // Finish going through all blocks.

	// Now, all the data is readily stored in the temporary data structures.
	*num_of_macro = num_macro;
	}


	int alloc_and_load_placement_macros(t_direct_inf* directs, int num_directs, t_pl_macro ** macros){

	/* This function allocates and loads the macros placement macros *
	* and returns the total number of macros in 2 steps. *
	* 1) Allocate temporary data structure for maximum possible *
	* size and loops through all the blocks storing the data *
	* relevant to the carry chains. At the same time, also count *
	* the amount of memory required for the actual variables. *
	* 2) Allocate the actual variables with the exact amount of *
	* memory. Then loads the data from the temporary data *
	* structures before freeing them. *
	* *
	* For pl_macro_member_blk_num, allocate for the first dimension *
	* only at first. Allocate for the second dimemsion when I know *
	* the size. Otherwise, the array is going to be of size *
	* cluster_ctx.clb_nlist.blocks().size()^2 (There are big *
	* benckmarks VPR that have cluster_ctx.clb_nlist.blocks().size() *
	* in the 100k's range). *
	* *
	* The placement macro array is freed by the caller(s). */

	/* Declaration of local variables */
	int imacro, imember, num_macro;
	auto& cluster_ctx = g_vpr_ctx.clustering();

	/* Allocate maximum memory for temporary variables. */
	std::vector<int> pl_macro_idirect(cluster_ctx.clb_nlist.blocks().size());
	std::vector<int> pl_macro_num_members(cluster_ctx.clb_nlist.blocks().size());
	std::vector<std::vector<ClusterBlockId>> pl_macro_member_blk_num(cluster_ctx.clb_nlist.blocks().size());
	std::vector<ClusterBlockId> pl_macro_member_blk_num_of_this_blk(cluster_ctx.clb_nlist.blocks().size());

	t_pl_macro * macro = NULL;

	/* Sets up the required variables. */
	alloc_and_load_idirect_from_blk_pin(directs, num_directs,
	&f_idirect_from_blk_pin, &f_direct_type_from_blk_pin);


	/* Compute required size: *
	* Go through all the pins with possible direct connections in *
	* f_idirect_from_blk_pin. Count the number of heads (which is the same *
	* as the number macros) and also the length of each macro *
	* Head - blocks with to_pin OPEN and from_pin connected *
	* Tail - blocks with to_pin connected and from_pin OPEN */
	num_macro = 0;
	find_all_the_macro (&num_macro, pl_macro_member_blk_num_of_this_blk,
	pl_macro_idirect, pl_macro_num_members, pl_macro_member_blk_num);

	/* Allocate the memories for the macro. */
	macro = (t_pl_macro ) vtr::malloc (num_macro sizeof(t_pl_macro));

	/* Allocate the memories for the chaim members. *
	* Load the values from the temporary data structures. */
	for (imacro = 0; imacro < num_macro; imacro++) {
	macro[imacro].num_blocks = pl_macro_num_members[imacro];
	macro[imacro].members = (t_pl_macro_member ) vtr::malloc(macro[imacro].num_blocks sizeof(t_pl_macro_member));

	/* Load the values for each member of the macro */
	for (imember = 0; imember < macro[imacro].num_blocks; imember++) {
	macro[imacro].members[imember].x_offset = imember * directs[pl_macro_idirect[imacro]].x_offset;
	macro[imacro].members[imember].y_offset = imember * directs[pl_macro_idirect[imacro]].y_offset;
	macro[imacro].members[imember].z_offset = directs[pl_macro_idirect[imacro]].z_offset;
	macro[imacro].members[imember].blk_index = pl_macro_member_blk_num[imacro][imember];
	}
	}

	/* Returns the pointer to the macro by reference. */
	*macros = macro;

	if(isEchoFileEnabled(E_ECHO_PLACE_MACROS)) {
	write_place_macros(getEchoFileName(E_ECHO_PLACE_MACROS), *macros, num_macro);
	}

	validate_macros(*macros, num_macro);

	return (num_macro);
	}

	void get_imacro_from_iblk(int imacro, ClusterBlockId iblk, t_pl_macro macros, int num_macros) {

	/* This mapping is needed for fast lookup's whether the block with index *
	* iblk belongs to a placement macro or not. *
	* *
	* The array f_imacro_from_iblk is used for the mapping for speed reason *
	* [0...cluster_ctx.clb_nlist.blocks().size()-1] */

	/* If the array is not allocated and loaded, allocate it. */
	if (f_imacro_from_iblk.size() == 0) {
	alloc_and_load_imacro_from_iblk(macros, num_macros);
	}

	/* Return the imacro for the block. */
	*imacro = f_imacro_from_iblk[iblk];

	}

	/* Allocates and loads imacro_from_iblk array. */
	static void alloc_and_load_imacro_from_iblk(t_pl_macro *macros, int num_macros) {
	int imacro, imember;
	auto& cluster_ctx = g_vpr_ctx.clustering();

	f_imacro_from_iblk.resize(cluster_ctx.clb_nlist.blocks().size());

	/* Allocate and initialize the values to OPEN (-1). */
	for (auto blk_id : cluster_ctx.clb_nlist.blocks()) {
	f_imacro_from_iblk.insert(blk_id, OPEN);
	}

	/* Load the values */
	for (imacro = 0; imacro < num_macros; imacro++) {
	for (imember = 0; imember < macros[imacro].num_blocks; imember++) {
	ClusterBlockId blk_id = macros[imacro].members[imember].blk_index;
	f_imacro_from_iblk.insert(blk_id, imacro);
	}
	}
	}

	void free_placement_macros_structs(void) {

	/* This function frees up all the static data structures used. */

	// This frees up the two arrays and set the pointers to NULL
	auto& device_ctx = g_vpr_ctx.device();
	int itype;
	if ( f_idirect_from_blk_pin != NULL ) {
	for (itype = 1; itype < device_ctx.num_block_types; itype++) {
	free(f_idirect_from_blk_pin[itype]);
	}
	free(f_idirect_from_blk_pin);
	f_idirect_from_blk_pin = NULL;
	}

	if ( f_direct_type_from_blk_pin != NULL ) {
	for (itype = 1; itype < device_ctx.num_block_types; itype++) {
	free(f_direct_type_from_blk_pin[itype]);
	}
	free(f_direct_type_from_blk_pin);
	f_direct_type_from_blk_pin = NULL;
	}
	}

	static void write_place_macros(std::string filename, const t_pl_macro *macros, int num_macros) {

	FILE* f = vtr::fopen(filename.c_str(), "w");

	fprintf(f, "#Identified Placement macros\n");
	fprintf(f, "Num_Macros: %d\n", num_macros);
	for (int imacro = 0; imacro < num_macros; ++imacro) {
	const t_pl_macro* macro = &macros[imacro];
	fprintf(f, "Macro_Id: %d, Num_Blocks: %d\n", imacro, macro->num_blocks);
	fprintf(f, "------------------------------------------------------\n");
	for (int imember = 0; imember < macro->num_blocks; ++imember) {
	const t_pl_macro_member* macro_memb = &macro->members[imember];
	fprintf(f, "Block_Id: %zu, x_offset: %d, y_offset: %d, z_offset: %d\n",
	size_t(macro_memb->blk_index),
	macro_memb->x_offset,
	macro_memb->y_offset,
	macro_memb->z_offset);
	}
	fprintf(f, "\n");
	}

	fprintf(f, "\n");

	fprintf(f, "#Macro-related direct connections\n");
	fprintf(f, "type type_pin is_direct direct_type\n");
	fprintf(f, "------------------------------------------\n");
	auto& device_ctx = g_vpr_ctx.device();
	for (int itype = 0; itype < device_ctx.num_block_types; ++itype) {
	t_type_descriptor* type = &device_ctx.block_types[itype];

	for (int ipin = 0; ipin < type->num_pins; ++ipin) {
	if (f_idirect_from_blk_pin[itype][ipin] != OPEN) {
	if (f_direct_type_from_blk_pin[itype][ipin] == SOURCE) {
	fprintf(f, "%-9s %-9d true SOURCE \n", type->name, ipin);
	} else {
	VTR_ASSERT(f_direct_type_from_blk_pin[itype][ipin] == SINK);
	fprintf(f, "%-9s %-9d true SINK \n", type->name, ipin);
	}
	} else {
	VTR_ASSERT(f_direct_type_from_blk_pin[itype][ipin] == OPEN);
	}
	}

	}

	fclose(f);
	}

	static bool is_constant_clb_net(ClusterNetId clb_net) {
	auto& atom_ctx = g_vpr_ctx.atom();
	AtomNetId atom_net = atom_ctx.lookup.atom_net(clb_net);

	return atom_ctx.nlist.net_is_constant(atom_net);
	}

	static bool net_is_driven_by_direct(ClusterNetId clb_net) {
	auto& cluster_ctx = g_vpr_ctx.clustering();

	ClusterBlockId block_id = cluster_ctx.clb_nlist.net_driver_block(clb_net);
	int pin_index = cluster_ctx.clb_nlist.net_pin_physical_index(clb_net, 0);

	auto direct = f_idirect_from_blk_pin[cluster_ctx.clb_nlist.block_type(block_id)->index][pin_index];

	return direct != OPEN;
	}

	static void validate_macros(t_pl_macro* macros, int num_macros) {
	//Perform sanity checks on macros
	auto& cluster_ctx = g_vpr_ctx.clustering();

	//Verify that blocks only appear in a single macro
	std::multimap<ClusterBlockId,int> block_to_macro;
	for (int imacro = 0; imacro < num_macros; ++imacro) {
	for (int imember = 0; imember < macros[imacro].num_blocks; ++imember) {
	ClusterBlockId iblk = macros[imacro].members[imember].blk_index;

	block_to_macro.emplace(iblk, imacro);
	}
	}

	for (auto blk_id : cluster_ctx.clb_nlist.blocks()) {
	auto range = block_to_macro.equal_range(blk_id);

	int blk_macro_cnt = std::distance(range.first, range.second);
	if (blk_macro_cnt > 1) {
	std::stringstream msg;
	msg << "Block #" << size_t(blk_id) << " '" << cluster_ctx.clb_nlist.block_name(blk_id) << "'"
	<< " appears in " << blk_macro_cnt << " placement macros (should appear in at most one). Related Macros:\n";

	for (auto iter = range.first; iter != range.second; ++iter) {
	int imacro = iter->second;
	msg << " Macro #: " << imacro << "\n";
	}

	VPR_THROW(VPR_ERROR_PLACE, msg.str().c_str());
	}
	}
	}